Lock means for pump chambers of fluid dispensing pumps



July 2, 1957 v STEELE 2,797,849

LOCK MEANS FOR PUMP CHAMBERS OF FLUID DISPENSING PUMPS Filed April 7, 1955 2O INVENTOR 20 Fl 6. VERNON P STEELE ATTORNEY 2,797,849 Patented .luly 2, 1957 Vernon P. Steele, Stamford, Conn.,-assignor to Kence Products Corporation, Englewood, N. J.

Application April 7, 1955, San No. 499,993 9 Claims. (31. 222-340 This invention relates to submersible syrup pumps, and, more particularly, to lock means for use with detachable pump chambers incorporating bayonet joint-securing means.

The bayonet joint mounting of valved pump chambers detachably subjoined to fixed mounting disks, while simple, and usually eifective when thin, free-flowing liquids are dispensed, does not function too well in the dispensing of the more viscous, syrupy flavorings, particularly under conditions where sustained volume of business necessitates substantially uninterrupted use of pumps. Under such sustained conditions, the spin and drag of viscous, syrupy liquids on the Walls of pump chambers as they are alternately filled and discharged, oftentimes at a rapid rate, imposes torsional forces on the chambers, resulting in the unseating of the bayonet jointed chamber from its support, and disruption of service.

Most pump chambers of the bottom-fill, disk-closure valve type are particularly susceptible to the above noted operative difficulty. This condition maybe due to the fact that the inflowing, syrupyliquid is inspirated through an axial opening into a pump chamber as a relatively flat, spinning body which wets and adheres to the walls of the chamber and applies a unidirectional circular twist or torque to the walls, as a result of the expanding inflow. On the discharge stroke, the normally spring-biased seating engagement of the bayonet joints of the chamber against their coacting locking pins on the support, is broken by the depression of the chamber as a result of the piston forcing the contained fluid, against the biasof the seating spring, out through the discharge tube. When the oscillatory motion of the chamber is reinforced by its vertical up-and-down reciprocation, which may occur due to the lag in such motions imposed by the drag of the syrupy, viscous liquid, the net result of the combination of forces is the untwisting and unseating of the bayonet joints from their cooperative engagement with their supporting pins. p

The phenomenon of the accentuated surface. tension of syrupy liquids will thus be seen to have a controlling bearin on the operation of syrup pumps under thecircumstances recited above. Correction of the situation by reduction of surface tension, as by watering or other dilution of syrups, is not practicable, either as an operative or as a business practice. H p I 1 An object of the present invention is to obviate the prior art difiiculties by providing means for locking engagement with bayonet joints of syrup pump chambers.

Another object of this invention is to provide a locking device for bayonet joints of members normally subject to conjoint oscillatory and reciprocatory moments of force which tend to break the joints.

Still another object of this invention is to provide means for locking syrup pump chambers in place on discharge pipes of syrup pumps.

A still further object of this invention is to provide a readily demountable, shake-proof bayonet joint construction for use in syrup pumps.

With these and other objects in view, which may be incident to my improvements, the invention consists in the parts and combinations to be hereinafter set forth and claimed, with the understanding that the several necessary elements, comprising my invention, may be varied in construction, proportions and arrangement, without departing from the spirit and scope of the appended claims,

In order to make my invention more clearly understood, I have shown in the accompanying drawings means for carrying the same intopractical eifect, without limiting the improvements in their useful applications to the particular constructions, which for the purpose of explanation, have been made the subject of illustration.

Figure 1 is an expanded elevational .view of a covermounted syrup pump embodying the improvements of the present invention;

Fig. 2 is an enlarged plan view of a syrup cup showing the locking device of the present invention;

Fig. 3 is afront view of the upper portion of the cup of Fig. 2; and

Fig. 4 is a vertical sectional view taken on line 4-4 of Fig. 2. I

Turning now to the drawings, the invention is shown in relation toits special incorporation and use in a submersible syrup pump. As shown in Figure 1, such a pump installation comprises a skirted cover 10, of any suitable configuration, fixedly mounting a delivery tube 11, and a subjoined stay rod 12. A pump actuating rod 13 is journaled in the cover and is adapted to be actuated by a depressible, spring-biased actuator 14. This actuator is specially disclosed and claimed in my pending applica tion Serial No. 293,057, filed June 12, 1952, for Adjustable Stroke Syrup Pump, now Patent No. 2,752,072.

The rods 12 and 13 are in mutual alignment with and are equidistant from the delivery tubell which has a discharge spout 15. The lower end of the discharge tube extends through, and is axially secured in, a foraminous supporting plate or disk 16 having a plurality of protruding radial knobs, lugs or fingers, designated generally by the numeral 17. The lower end of pump rod 13 isjournaled in the disk, and the lower endof stay rod 12 is fixedly secured therein by silver solder 18, as is the delivery tube. The tube 11 depends into the cup, with its bottom spaced a short distance from the bottom of the cup.

A cup-shaped pump chamber 20 is provided with an axial bottom inlet 21 and a cylindrical wall 22 having a plurality of bayonet joint slots, designated generally by the numeral 23, radially disposed in the rim ofv the cup. These slots comprise spaced vertical slots 24, 25, joined at the bottom of a transverse slot 26. Each slot 24 is open at the top and is provided with opposed grooves 27 adjacent the top. The slots 23 normally-engage locking lugs 17 of fixed disk 16, the cup being twisted thereon to lock it in place. A fiat disk 28 overlies axial inlet 21 and serves as a flap valve, the valve eing maintained in desired position in its vertical movement by the. cage 28', formed by arms 29', welded or otherwise attached to the body of the valve. A second disk 29, adapted for slip fit reciprocation in pump chamber 20, is fixedlyyse cured 0111 16 bottom endof pump rod 13 and isreciprocable. therewithand thereby,serying asth'e pump piston.

I The special novel feature of this invention is the novel locking member 30,'sliown in the plan view ip Fig Z. This member is a flat, generally rectangular, 'bifurcate member having an intermediate, elongated opening 31, adapted for loose-fitting, sliding, tilting engagement on and over pump rod 13. One end 32, is cut out to form a curviform surface conformed to and adapted for sliding engagement on and with delivery tube 11. The other end is axially slotted at 33, to form, with opening 31 with which it is integral, bilateral legs 34, 35. These elements are cut back to form shouldered portions 36, 37, and fingers 38, 39, adapted for spring-gripping fit and engagement in and with grooves 27, of slots 23, supra. Because of the elongated opening 31, the member 30 can be tilted up and along and over the pump rod and the spring fingers 34, 35, engaged with the grooves 27. On moving member 30 down at an angle along the delivery tube, the fingers 38, 39, are inserted into the grooves 27, in snapfit engagement, the cut-out portion 32 having loose fit with the delivery tube 11.

It will be noted that the bottom of the cup is inwardly dished to provide a seat for the valve 28, whereby efiective sealing is obtained between the valve and the fiat annulus forming the periphery of the opening 21. In conventional cups, the bottom is usually fiat, and as a consequence the outer periphery of the flap valve seats in the arcuate juncture between the wall and bottom of the cup, with the result that there is a very poor seal between the valve and the opening into the cup. In applicants arrangement close contact between the valve 28 and its seat is obtained, regardless of the angularity of the axis of the cup with respect to the horizontal, or whether or not the valve is restrained to movement in a vertical path. In this connection, it will be appreciated that pumps of the type disclosed herein, are usually mounted on containers positioned in a cabinet or rack at an angle of approximately 45 to the horizontal, and accordingl there is a decided tendency for the flap valve to slide into a position which will prevent good sealing contact.

The emplacement and removal of member in and from its cooperative engagement with the delivery tube and the pump chamber is effected most simply, and by mere manipulation with the fingers, no tools being required. The positive inter-locking of the detachable pump chamber with its supporting means 16, insures continued and uninterrupted operation of a syrup pump, due to freedom from break-down and shaking or twisting loose of the chamber from its mounting.

The novel locking member is adapted for use with all types of bayonet joint-supported pump chambers which are subject to the unseating action of swirling bodies of inflowing and outflowing syrupy liquids, or the like, which are characterized by a high surface tension. Such liquids, when flowed, under pressure, between confining surfaces, exert a positive drag on any surfaces with which they are dynamically contacted, which drag, as noted, is too often translated into a pump chamber-unseating torque.

While I have shown and described the preferred embodiment of my invention, I wish it to be understood that I do not confine myself to the precise details of construction herein set forth by way of illustration, as it is apparent that many changes and variations may be made therein, by those skilled in the art, without departing from the spirit of the invention or exceeding the scope of the appended claims.

What is claimed:

1. In a syrup pump having a piston reciprocable by a piston rod in a submerged valved cup detachably subjoined to and locked on a supporting disk by at least one bayonet joint, the disk being fixedly subjoined to the pump cover and unitary therewith, the improvement comprising a locking member engageable in the bayonet joint slot after the cup is locked on the disk, whereby the cup is prevented from being unseated in the bayonet joint due to undesired shaking and torsions resulting from swirling of liquid in the valved cup on reciprocation of the piston therein.

2. A syrup pump according to claim 1, characterized by the fact that the locking member is fiat and is freely reciprocable on the piston rod.

3. A syrup pump according to claim 2, characterized by the fact that the locking member is formed with stub fingers at its bayonet joint-engaging end, and is adapted for spring-gripping engagement in and with the said joint.

4. A syrup pump according to claim 3, characterized by the fact that the bayonet joint incorporates snap-lock engaging means adapted to receive the fingered end of the locking member.

5. A syrup ptunp according to claim 1, characterized by the fact that the cup incorporates a plurality of radial bayonet joint slots, and the supporting disk is formed with a like number of radial fingers engageable in and by the said slots, and one bifurcate key is associated with the disk and engageable in one of the slots.

6. A locking member, as and for the purpoes described. comprising a generally rectangular, fiat member having an arcuate cut-out at one end, an axial longitudinal slot at the other end, and an axial opening intermediate the said ends, and reduced finger portions at the slotted end.

7. A syrup pump having a cover detachably mounting a spring-biased pump rod and fixedly mounting a delivery tube and a stay rod, the said rods and tube being aligned, with the rods on either side of the tube; a submersible pump mechanism spacedly subjoined to the cover, comprising a supporting, foraminous disk fixedly and axially mounted on the bottom end of the delivery tube, and radially fixedly mounted on the bottom end of the stay rod, the disk having an opening diametrically aligned with the axial tube and the stay rod and adapted to journal the pump rod; a valved cup-shaped pump chamber detachably subjoined to and on the said disk; a piston mounted for reciprocation in the pump chamber and integral with the bottom of the pump rod, the piston being normally spring-biased into its up, chamber-filled position; a plurality of bayonet joint slots formed in the rim of the cup; a like number of radial fingers extending from and integral with the disk, said fingers being engageable in said slots and locked therein on rotation of the cup thereover; and lock means comprising a bifurcate, fiat key slidable on the piston rod with one end conformed to the delivery tube and slidable therealong, and the other end adapted to be received in a bayonet slot when the cup is locked in place on the disk, whereby the cup is prevented from being unseated in the bayonet joints due to undesired shaking and torsions resulting from swirling of inflowing and outflowing syrupy liquid in the valved pump chamber on reciprocation of the piston therein.

8. A syrup pump according to claim 7, characterized by the fact that the bayonet joint-engaging end of the bifurcate key is fingered, whereby to lockingly engage a bayonet joint slot.

9. A syrup pump according to claim 8, characterized by the fact that the bayonet joint slots are formed with key-receiving grooves adapted to receive the fingered ends of the bifurcate key in snap-locking engagement.

References Cited in the file of this patent UNITED STATES PATENTS 

